A federal court in Alabama recently issued an interesting decision on defendant’s motion to exclude plaintiff’s expert evidence in a medical device case.  See Lowery v. Sanofi-Aventis LLC, 2021 WL 872620 (N.D. Ala. Mar. 9, 2021).

Plaintiff advanced claims based on the allegation that he suffered injuries after Defendant’s medical device, Synvisc-One, was injected into his right knee. Plaintiff alleged that a contaminant caused septic arthritis (i.e., a joint infection) in his right knee and other injuries resulting from the onset of septic arthritis, including hearing loss, reduced mobility, and a shortened lifespan. To establish that the bacteria caused septic arthritis and other injuries, Plaintiff was prepared to offer the testimony of Dr. Charles Abney. And, to testify that Defendant’s manufacturing processes and facilities violated federal regulations, Plaintiff offered Dr. Catherine E. Patterson. Defendant challenged the admissibility of both witnesses’ opinion testimony. 2021 WL 872620, at *1.

The Court concluded that Dr. Abney’s opinions were inadmissible for three reasons. First Dr. Abney did not have the knowledge, skill, experience, training, or education to proffer his opinions in this case. Second, he did not employ reliable methods in reaching his conclusions. Third, his opinions failed to assist the trier of fact.  The Court further determined that Dr. Patterson’s expert opinion testimony on the regulatory matters was  inadmissible for two reasons. First, her conclusions that Defendant’s procedures were not in compliance with FDA regulations lacked reliable analysis. Second, even if her opinions were based on reliable scientific methods, they related to preempted issues and thus would not assist the trier of act. Thus, Defendant’s Motions were granted.
Specifically, experts may be qualified to provide opinion testimony in various ways, including training, education, or experience in a given field. Often the issue raised under the qualification prong is not whether the proffered expert is qualified in a general field but whether his training, education, or experience qualify him to render an opinion on a specific “issue before the court.” Jones v. Novartis Pharm. Corp., 235 F. Supp. 3d 1244, 1251 (N.D. Ala. 2017). Particularly where an expert’s qualifications rest on his experience (as opposed to education or training), the expert “must explain how that experience leads to the conclusion reached, why that experience is a sufficient basis for the opinion, and how that experience is reliably applied to the facts.” United States v. Frazier, 387 F.3d 1244, 1261 (11th Cir. 2004) (en banc) (citing Fed. R. Evid. 702). The court cannot simply take the expert’s word for it. Id. Sometimes, an expert’s credentials raise credibility issues, but do not affect admissibility. Maiz v. Virani, 253 F.3d 641, 666 (11th Cir. 2001); Rushing v. Kansas City S. Ry. Co., 185 F.3d 496, 507 (5th Cir. 1999). Nonetheless, a court must always determine whether an expert is qualified to testify to the subject matter at issue.  Kilpatrick v. Breg, Inc., 2009 WL 2058384, at *3 (S.D. Fla. June 25, 2009).

This is one notion of “fit.”  A medical doctor is not qualified to opine on all areas of medicine by virtue of having a medical license or practicing in one area of medicine. See Hendrix v. Evenflo Co., 255 F.R.D. 568, 578 (N.D. Fla. 2009), aff’d sub nom., Hendrix ex rel. G.P. v. Evenflo Co., 609 F.3d 1183 (11th Cir. 2010). Another district court analogized that “just as a lawyer is not by general education and experience qualified to give an expert opinion on every subject of the law, so too a scientist or medical doctor is not presumed to have expert knowledge about every conceivable scientific principle or disease.” Whiting v. Bos. Edison Co., 891 F. Supp. 12, 24 (D. Mass. 1995); see Alexander v. Smith & Nephew, P.L.C., 98 F. Supp. 2d 1276, 1281 (N.D. Okla. 2000) (possession of a medical degree and emergency room experience was insufficient to testify to “the advantages of a spinal fixation device, the medical causation of spine-related ailments, or the mechanical functioning of an orthopedic implantation device”).  In accordance with that line of case law, Dr. Abney was unqualified to testify that Plaintiff in fact had septic arthritis because he lacks specialized training, education, and experience regarding that medical issue.  There was no evidence that Dr. Abney had the expertise needed to reliably assess whether Plaintiff’s reaction was septic versus pseudoseptic.  Except during an approximately two-month long rotation during his residency (which was not in orthopedics and was over twenty years ago), he had never administered Synvisc-One, had never performed any orthopedic procedure on a patient’s knee, had never completed any training in orthopedics, and had never (at any time) researched or written on the subjects of treating osteoarthritis, knee replacements, injections, Synvisc-One, knee infections, or pseudoseptic reactions.  2021 WL 872620, at *8.

Related to this, the Court explored a very useful distinction between testimony about a patient’s condition, and opinions about the cause of that condition.  In Harvey v. Novartis Pharm. Corp., the court held that a maxillofacial surgeon, who had “no experience in identifying the specific cause” of the diagnosed condition at issue, was incompetent to opine on the issue of causation. 895 F. Supp. 2d 1206, 1211-12 (N.D. Ala. 2012) (citing Thomas v. Novartis Pharm. Corp., 443 F. App’x. 58, 63 (6th Cir. 2011)). The surgeon, while eminently qualified to testify “within the ordinary expertise of maxillofacial surgeons” and generally knowledgeable of the condition, did not have any practical experience in identifying the cause of the condition at issue in that case. Id. That is, mere expertise about treatment of a condition simply does not equate to expertise about what causes that condition. Id.
Indeed, the Harvey result is not an outlier. See Jones, 235 F. Supp. 3d at 1292 (holding that treating physician and board-certified orthopedic surgeon was not competent to opine on cause of femur fracture).

Next, because the ultimate issue in this case was whether a contaminant caused Plaintiff’s injuries, this was akin to a toxic tort case that requires expert testimony to establish two types of causation: general and specific. General causation is established by an expert “laying a scientific groundwork” that the toxin in question “can cause the harm plaintiff alleges.”  Chapman v. Procter & Gamble Distrib., LLC, 766 F.3d 1296, 13o3 (11th Cir. 2014).  Specific causation, secondly, requires a court to evaluate whether the expert’s methodology reliably concludes that the “substance ‘caused the plaintiff’s specific injury.’ ” Id.  But,  the Curt concluded, Dr. Abney’s medical causation opinion testimony was inadmissible because (1) he failed to conduct or rely on reliable scientific groundwork before arriving at his conclusions regarding Plaintiff’s condition; and (2) his specific causation analysis was not the product of reliable methods and analysis.  2021 WL 872620, at *12. Dr. Abney admitted that he did not know the propensity of Methylobacterium thiocyanatum to cause septic arthritis and (before this case) that he had not heard of Methylobacterium thiocyanatum.  He also conceded that exposure does not “automatically” result in an infection.  At the same time, Dr. Abney was aware that a pseudoseptic reaction is a known side effect of Synvisc-One and can cause symptoms like septic arthritis.

While some courts have held that differential diagnosis (that is, differential etiology) is reliable for determining medical causation., there are two steps in a proper “process of elimination” differential diagnosis: (1) the expert rules in “the possible causes of a condition”; and (2) the expert then arrives at a cause by ruling out the possible causes “one-by-one, leaving only one cause remaining.” E.g., Hendrix, 609 F.3d at 1198. An expert must consider the most relevant potential causes, and must provide a “reasonable” explanation for eliminating other causes under the circumstances and cannot “simply” claim that he “performed a differential diagnosis.”  Such a “process,” that wholly fails to provide a reasonable explanation, is not a method at all but rather a substitution of the expert’s own assertion for the scientific method (the “ipse dixit”). Dr. Abney relied on “the temporal sequence” between the injection and the onset of symptoms, but temporal proximity is not a reliable indicator of causation as it “leads to the blunder of the post hoc ergo propter hoc fallacy.” This is particularly true where, as here, Dr. Abney admitted that the “onset of pain and swelling” could be a sign of septic arthritis or a pseudoseptic reaction.  2021 WL 872620, at *14.

Turning to the second expert, despite her statement that her methods analyze the GMPs and other federal requirements, Dr. Patterson failed to explain which GMPs that Defendant has violated, let alone how Defendant’s conduct or processes violate them. Without any analysis connecting the facts to the conclusions in her report, her opinions amount to little more than her personal beliefs.  This same analysis applied to her conclusion that the Lot in question was not “sterile” and “would be considered adulterated by the FDA.”  With respect to guidance documents or other supporting materials, Dr. Patterson made an impermissible logical jump and contended that Defendant’s deficiencies in those documents are themselves violations of the GMPs. Yet, such guidance documents are not binding rules or regulations but recommended procedures. The same lack of analysis existed for Dr. Patterson’s list of problems related to equipment maintenance, procedures, and historical manufacturing deficiencies where she listed her criticisms and cited generally to an FDA guidance document. 2021 WL 872620, at *19–20.

Dr. Patterson’s opinion testimony that Defendant should have conducted additional testing did not assist the trier of fact in this case for two reasons. First, Dr. Patterson’s opinion that Defendant should have implemented different testing methods that are not compelled by a federal law would go, at best, to a theory of liability that is preempted and, for that reason, cannot be an issue put to the jury at trial.  This same analysis applied to Dr. Patterson’s other criticisms of Defendant’s facilities and manufacturing practices. Her lack of support connecting Defendant’s alleged actions to binding federal requirements would leave it to the fact-finder to bridge the gap in her analysis (and, furthermore, would otherwise be directed to issues preempted by federal law).  Second, Dr. Patterson’s conclusion that the deficient tests “could” have led to false negatives shows the equivocal nature of her opinion and would not assist the jury in finding causation by a preponderance of the evidence. 2021 WL 872620, at *21–22.